Experimental Research Of The Treatment Of Tracheal Stenosis With The Acellular Dermal Matrix

Laryngostenosis and tracheostenosis are common clinical diseases. People withlaryngostenosis or tracheostenosis feel breathing difficulty. And they usually needtracheotomy. So, patients with laryngostenosis or tracheostenosis feel very painful. One ofthe leading causes of laryngostenosis and tracheostenosis is the defect of the trachealmucosa. Therefore, to prevention and treatment of tracheal stenosis, we should timely andeffectively repair of the tracheal mucosal defect. At present, the main methods of repair oftracheal mucosal defect are autograft transplantation and transfer of mucosa flap.Autologous transplantation often uses the oral mucosa, sinus mucosa or nasal septummucosa. However, autograft transplantation and transfer of mucosa flap makes someproblems. For example, the limited of mucosa, increasing patient’s pain when the mucosa was removed. With the development of tissue engineering, ADM has been successfullyapplied to repair oral mucosa, vocal cord, abdominal wall and so on. In this experiment,we will use ADM to repair canine with large defects in tracheal mucous. We will observatethe repair effect of canine tracheal mucosa. We plan to using ADM in a caninetracheostenosis model to confirm its efficacy on treatment of tracheal stenosis.OBJECTIVE1. To confirm the defect of tracheal mucous with20mm×25mm will cause trachealstenosis by Wang zhi’ tracheal stenosis model. We will cut the second tracheal ring tothe sixth tracheal ring. And we will remove the tracheal mucosa with an area of20mm×25mm.2. To observe the healing process of dog’s tracheal mucosal defect repaired with theheterogeneous acellular dermal matrix, and to study the mechanism of heterogeneousacellular dermal matrix in promotion the repair of tracheal ciliated epithelium andinhibiting scar formation.METHODS1. A model of canine tracheal stenosisWang Zhi’ model of canine tracheal stenosis was used in this experiment. We will cut thesecond tracheal ring to the sixth tracheal ring along the midline deviation15mm to theright. And we will remove the tracheal mucosa with an area of20mm×25mm. Keep thetracheal cartilage membranes intact.2. The efficacy of ADM in preventing tracheal stenosis10dog’s model with circumferential tracheal mucosa defect of20mm×25mm was dividedrandomly into two groups. The defect of the mucosa covered with heterogeneous acellulardermal matrix was the experimental group. The control group was covered was nothing.The animals were sacrificed two, four, six, eight and ten weeks postoperatively. Thehealing process of denuded area was observed by macroscopic view, electronlaryngoscopeexamination, HE and Masson staining, scanning electron microscope. RESULTS1. A model of canine tracheal stenosisTen canines successfully operated. For the control group, we can observe varying degreesof repairing scar as time prolonged. At8weeks, we can observe obvious tracheal stenosiswith a laryngoscope.2. The efficacy of ADM in preventing tracheal stenosisAll animals survived to the end of the study. For the experimental group, wounds werecovered by ciliated epithelium at four weeks and hypertrophic scar wasn’t observed at tenweeks.CONCLUSION1. The model of canine trachealstenosis induced by removing the tracheal mucosa with anarea of20mm×25mm is a reliable and reproducible animal model.2. This experiment demonstrated that the heterogeneous acellular dermal matrix couldeffectively promote the repairing process of epithelium mucosa defect in trachea, preventformation of cicatricial stenosis and get an excellent epithelization on the wounds.